Whale sharks worse off in worst-case Ningaloo oil spill model

WAToday (Asutralia) : Whale sharks worse off in worst-case Ningaloo oil spill model

Ningaloo's world famous whale sharks would be the creatures most at risk should a crude oil spill occur at Royal Dutch Shell's proposed well next to the marine park.

Shell, one of the world's biggest resources companies, announced plans to develop the Prelude liquefied natural gas venture and explore for oil and gas in the Exmouth basin off the WA north-west coast on Monday.

Although the company has played down fears over any oil spill or gas leak coming from an exploration well being located less than 50 kilometres from the marine park, it suggested that whale sharks would suffer the greatest exposure since they undertake long migrations to feed in the waters off Ningaloo.

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An image from Shell's application showing what it claims would be a worst-case oil leak scenario off the WA coast.

The creatures' food source could be compromised but it suggested any spill would take 560 hours to reach the Ningaloo reef system.

The impacts to turtles, dolphins, whales, dugongs, sharks, fish and birds were also not discounted, with "sub-lethal impacts such as minor adherence, irritation and absorption" possible through exposure.

A worst-case scenario showed a spill of 70,000 gallons (bbls) a day escaping onto the seabed for 77 days was more likely to reach turtles' nesting beaches around the North West Cape and Murion Islands than most other parts of the coast, but these impacts were still considered a "low probability" by the company.

A leak of the size that recently hit the Montara oil well off the northern WA coast in the Timor Sea could cause irreparable damage to the unique environment, which has been nominated for UNESCO world heritage listing, according to environmental groups.

But modelling by Shell suggested tidal movements and water current would cause spills to travel to deeper water away from or parallel to the Ningaloo Reef.

Acting Premier Kim Hames agreed, saying there were already up to eight wells in operation north of Ningaloo and that "50ks from the reef is no more or less likely to get it than 100ks".

Dr Hames said it was important the state government be able to control and have input over the development of the well to meet strict environmental standards.

"The state than has the process of assessing safety features around it applying conditions to ensure safety. We want to make sure Ningaloo reef as a system is protected and we have concerns because of oil spills we have seen around the world.

"... It certainly causes concern but only if you're aware of the safety conditions that applied for Montara and whether or not if they would be the same as the ones applied to Ningaloo Reef.

"My view is that they are not and I don't think the state government was able to set the conditions for Montara because it was well out of Western Australian space.

"This is in Western Australian space and this is where the state has the final say.

"The Commonwealth Government, as I am sure you know, is proposing to have a national system of approval controlled by the Commonwealth. That's something we are opposing because we believe the states' are best placed to look at issues like this and make a determination about whether it is in the best interest of Western Australians."

Shell has made an application to drill an initial test well to a depth of 5650 metres as early as September.

It claimed that it was most likely to discover gas rather than heavy oils and was assembling a globally deployable well-capping system for the project.

It must receive ''all necessary environmental and safety approvals'' before it can proceed with the drilling and timing of the drilling depends on rig availability.

The company received preliminary Australian government approval for the venture in November.